Known motor vehicles of a certain size are often equipped with wheels of relatively large dimensions, which increase the driving comfort of the motor vehicle and offer a higher load capacity. At the same time, it is possible to observe a trend toward larger front-wheel-drive systems, usually in the form of transversely-installed internal combustion engines, wherein the motor vehicle body or structure should be as narrow as possible for aerodynamic reasons. This has the result that a space for the wheels is reduced in size, which conversely means that a maximum possible steering angle for example of front wheels is reduced.
A trend is also observed leading to motor vehicles with longer wheelbases combined with the transversely-installed internal combustion engine. This configuration enlarges the possible interior space of the motor vehicle and at the same time improves the driving comfort. A longer wheelbase, however, likewise reduces a possible steering radius.
In order to solve the above-stated problems, it is for example possible for all-wheel steering to be used. This, however, requires a steerable rear axle which loads the rear wheel suspension with additional weight and requires additional components for the rear wheel suspension. Such a system also requires some type of computer control, since the steering behavior of the rear wheels must be adapted both in terms of magnitude and direction as a function of the motor vehicle speed and other parameters.
EP 1 426 203 B1 discloses a method and a control element arrangement for adjusting the wheel track for a steerable vehicle arrangement. The arrangement has a steering adjustment member and a steering adjustment mechanism for transmitting steering movements from the steering adjustment member to a wheel hub and from the steering adjustment member to a wheel hub and a control arm, with the control arm being pivotably fastened at a first end to the vehicle and being provided with a ball joint. The ball joint is pivotably fastened to the wheel hub at a second end. An actuation of the steering adjustment mechanism causes a displacement of the ball joint by a predetermined path along an axis which runs substantially transversely with respect to a central longitudinal axis of the vehicle. The path is proportional to a vehicle wheel steering angle. The steering adjustment member acts on a controllable lever arm which is rotatable about a center of rotation on a wheel suspension control arm. The controllable lever arm acts on a pair of connecting rods which are pivotably fastened to the lever arm at opposite sides of the center of rotation on the lever arm, and to the wheel hub at opposite sides of the ball joint.
The method and the control member arrangement as per EP 1 426 203 B1 is advantageous in that a steering circle radius of the steer angle can be reduced by virtue of the centers of rotation of the wheels being moved away from disturbing components of the motor vehicle, so that larger steering angles can be obtained. In addition, the positional change of the wheels when the latter are steered results in a wider track for the steerable wheels, resulting in the handling of the motor vehicle when traveling around curves being improved. The subject matter of EP 1 426 203 B1 therefore has a positive effect both on the steer angle and also on the dynamic handling of the motor vehicle.